> You can force it by the geometry manager:
>
> pack [ttk::progressbar .t -value 30] -expand yes -fill both
>
> Just tried that you can adjust the size as you wish under Windows. But
> as others said, you should be careful not to disturb the native look.
>
> Christian
Yes, that seems to be the right direction.
But I still have a problem, as I want to make the thickness thiner than the standard thickness:
If I pack the progress bar directly into the main window, the thickness will be very big.
If I pack the progress bar in one of the sub-frames, the thickness never gets thinner than the standard value.